4 DIN system expansion interface Cable Accessories means the battery voltage is

means the battery voltage is low

This Harmony RM22-TR relay allows monitoring of phase and undervoltage/overtage in 3-phase networks

It is compatible with TT and TN-S earthing system

Battery reverse polarity protection

Experience streamlined power management with the DBSet 12 module VTPN distribution board designed for surface mounting

4 DIN system expansion interface Cable Accessories means the battery voltage isSystem expansion interface with modular 4 DIN housing. It enables doubling of the length of the entrance panel handset line, to create independent audio risers, and to expand the range or functions of the apartment system. The device must be configured using physical configurators More Product Details